Gamers are meticulous when it comes to designing their systems with power V-cards that handle more of the display functions, though they prefer speed for the transfer of information to the display(smaller amounts of info FAST & FREQUENT) Cooling is important for these cards. Graphics rely on more stable cards for larger amounts of Info in short infrequent frames.

These cards relieve the processor of heavy tasking. However it is noticable when the software is using (like you mentioned) 98% of resource.  Then consider the amount of info that crosses the bus to write to a file and send info to the display device together. Your system resource monitor will still show almost maximum usage though it has to dole out 2 processes, or more.

When I owned just one machine, I would have to sit in the other room while renders dominated my system. So I opted to split up my expense on two rather than dump it all into one system(even if it was a kick ass system).

I still on occasion multi task myself into a crash.....(Traffic Jam on the circuit board highway)!! 

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Ockham's razor- It's that simple